Gas and heat protective garment

ABSTRACT

A gas and heat protective garment comprises a suit provided with pipes for circulation of a cooling medium and a knapsack housing a respiration protecting system and a refrigerating unit including among other components a pneumatic pump and a reservoir with a liquid refrigerant. There is a gas cushion in the refrigerant reservoir, which gas cushion is put in communication with the pneumatic pump through a vapour pipe a portion of which is arranged to extend above the level of the liquid refrigerant in the reservoir and is movably mounted in said reservoir, being adapted to remain in a vertical position when the reservoir changes its attitude. Owing to this constructional arrangement the vapour pipe always extends above the level of the liquid refrigerant when the wearer of the garment inclines, whereby only refrigerant vapour is permitted to pass into the pneumatic pump. This improves the operating dependability of the garment refrigerating unit and increases the range of garment use.

Rybalko et al.

[ GAS AND HEAT PROTECTIVE GARMENT [76] Inventors: Alexei PetrovichRybalk0,ulitsa Krasnooktyabrskaya, 77, kv. 62.; Viktor VladimirovichKarpekin, ulitsa Artema, 163a, kv. 24.; Nikolai Sidorovich Didenko,ulitsa Artema, 159, kv. 129.; Ivan Ivanovich Volokhov, ulitsa Artema,163, kv. 12., all of Donetsk, U.S.S.R.

[22] Filed: Apr. 24, 1974 [21] Appl, No.: 463,845

[30] Foreign Application Priority Data May 3,1973 U.S.S.R 1913869 [52]U.S. Cl 62/178, 62/179, 62/259, 62/514, 165/46, 128/379, 128/399 [51]Int. Cl. F25d 17/00 [58] Field of Search 62/259, 177, 178, 179, 62/514;165/46; 128/379, 399

[56] References Cited UNITED STATES PATENTS 2,984,994 5/1961 Hankins62/259 2,990,695 7/1961 Leffingwell 62/259 3,117,426 1/1964 Fischer62/259 3.211.216 10/1965 Coleman 165/46 3,526,102 9/1970 Boylett 62/2593,738,367 6/1973 Hardy 128/379 I i t 24 //III! 'llllll IllllllllllllMar. 11, 1975 Primary E.raminer-William J. Wye Attorney, Agent, orFirmEric H. Waters ABSTRACT A gas and heat protective garment comprisesa suit provided with pipes for circulation of a cooling medium and aknapsack housing a respiration protecting system and a refrigeratingunit including among other components a pneumatic pump and a reservoirwith a liquid refrigerant. There is a gas cushion in the refrigerantreservoir, which gas cushion is put in communication with the pneumaticpump through a vapour pipe a portion of which is arranged to extendabove the level of the liquid refrigerant in the reservoir and ismovably mounted in said reservoir, being adapted to remain in a verticalposition when the reservoir changes its attitude. Owing to thisconstructional ar rangement the vapour pipe always extends above thelevel of the liquid refrigerant when the wearer of the garment inclines,whereby only refrigerant vapour is permitted to pass into the pneumaticpump. This improves the operating dependability of the garmentrefrigerating unit and increases the range of garment use.

7 Claims, 6 Drawing Figures 25 3/ I A' H PATENTED MRI 1 5 sum 2 0g 4 3mums l ATENTED SHEET u E g GAS AND HEAT PROTECTIVE GARMENT The presentinvention relates to man individual protective means and, orparticularly, to gas and heat protective garments.

The invention provides protection in irrespirable atmospheres at ambienttemperatures up to 150 and can be used with advantage for rescue andrecovery jobs in metallurgical, chemical and mining industries, as wellas for fighting fire in mines.

Known is a gas and heat protective garment whose heat insulating coveraccommodates a suit provided with pipes for circulation of a coolingmedium and a knapsack housing a respiration protecting system and arefrigerating unit comprising a reservoir with a liquid refrigerant anda heat exchanger to abstract heat from the cooling medium circulatingthrough the suit pipes, the circulation of said cooling medium beingcaused by a pneumatic pump actuated by refrigerant vapour coming from agas cushion in the reservoir via a pipeline incorporating a pressureregulator.

The suit under consideration also has gloves, socks and a helmetarranged to leave the wearers face open. The heat insulating cover isworn over the suit and has a window at the wearer's face.

In such a garment the refrigerant is liquid ammonia and the coolingmedium is water.

The respiration protecting system of the garment under consideration isarranged in the form of a selfcontained oxygen breathing apparatuscomprising a breathing bag connected by means of hoses with an oxygenbottle, a regenerating cartridge and a mask. The hoses which connect themask with the breathing bag and the regenerating cartridge incorporateinhalation and exhalation valves.

The heat exchanger incorporated in the refrigerating unit of theprotective garment under consideration is constructed in the form of apipe located on the surface of the refrigerant reservoir. Part of theheat exchanger is located inside the breathing bag for the purpose ofcooling the regenerated air being inhaled.

The pneumatic pump included in the refrigerating unit has a housingwhich accommodates a bellows with a spring located therein. The interiorof the bellows communicates with the suit pipes and the heat exchangerthrough hoses which are each provided with a valve arranged to open andclose alternately in accordance with the bellows movement during thesuction and discharge of the cooling medium. The bellows has a bottomplate against which said spring fits. Attached to the outside of thebellow bottom plate is a rod connected to a linkage adapted to operate avalve fitted in the pump housing, said valve periodically putting thepump interior in communication with the atmosphere. The pump interiorcommunicates through a pressure regualtor with a gas cushion formed inthe reservoir by refrigerant vapour. Said pressure regulator isconstructed in the form of a shut-off valve accommodated in a housingand loaded by a spring the tension of which is set by the use of anadjusting screw. The adjustment of the spring governs the force holdingthe shut-off valve against its seat and, consequently, the actuatingpressure of the refrigerant vapour.

While the garment under consideration is being worn, the pressure of therefrigerant vapour in the reservoir changes under the influence of theambient temperature and also due to the fact that the shut-off valve ofthe pressure regulator is acted upon by the reservoir vapour pressure onone side and by the pneumatic pump interior pressure on the other side,said pump interior pressure periodically altering during the operationof the pump. Inasmuch as the pressure regulator spring is set to acertain reservoir vapour pressure, the pressure regulator comes intoaction only when a certain pressure differential acts upon the shut-offvalve. This constitutes one of the disadvantages of said pressureregulator. Moreover, the shut-off valve effective area acted upon by therefrigerant vapour pressure is comparatively small and, therefore, it isdifficult to effect smooth adjustment of the pressure regulator. Thisdisadvantage eventually results in a change of refrigerant vapourpressure in the reservoir with a consequent change of refrigerantevaporation point end the temperature of the cooling medium.

In the protective garment under consideration the construction of thepneumatic pump suffers from a number of disadvantages.

One of the disadvantages is that said pump linkage is subject to shockloads during operation and is, therefore, prone to wear cut rapidly,adversely affecting the life and dependability of the pump.

A further disadvantage is that the output of the pneumatic pump dependson the pressure of the refrigerant vapour in the reservoir. When thevapour pressure drops, the rate of evaporation increases and the pumpoperates at a faster rate, its output increasing. When the pressure ofrefrigerant vapour in the reservoir rises, the reverse takes place.Since the pump output is not constant, the temperature of the coolingmedium cannot be regulated smoothly. Furthermore, during suction anddischarge the pressure of the cooling medium in the suit pipes variesperiodically.

The protective garment under consideration suffers from the disadvantagethat the pipeline connecting the gas cushion in the reservoir to thepneumatic pump is fixedly mounted in the reservoir. When the wearerinclines, the liquid refrigerant gets into said pipeline, passes intothe pressure regulator and thence into the pneumatic pump, wherefrom itis exhausted into the atmosphere. The resultant waste of the refrigerantshortens the useful working time of the garment. Besides, the liquidrefrigerant (ammonia) evaporates on getting into the pneumatic pumpportion communicating with the atmosphere. Since the evaporation of therefrigerant is accompanied by intensive absorption of heat, thetemperature inside the pneumatic pump drops down to -34 C (the boilingpoint of liquid ammonia at atmospheric pressure). At this temperaturethe cooling medium contained in the bellows freezes and the protectivegarment ceases functioning.

It is an object of the present invention to increase the scope andimprove the dependability of the gas and heat protective garment.

This and other objects are achieved by providing a gas and heatprotective garment whose heat insulating cover accommodates a suitprovided with pipes for circulation of a cooling medium, a knapsackhousing a respiration protecting system, and a refrigerating unitcomprising a reservoir with a liquid refrigerant and a heat exchanger toabstract heat from the cooling medium circulating through the suitpipes, the circulation of said cooling medium being caused by apneumatic pump actuated by refrigerant vapour coming from a gas cushionin the reservoir via a pipeline incorporating a pressure regulator.

According to the invention, said pipeline is provided with a vapour pipea portion of which extends above the level of the liquid refrigerant andis movably mounted in the reservoir so that it remains in a verticalposition when the refrigerant reservoir changes its attitude. Thisarrangement permits only refrigerant vapour to pass to the pneumaticpump.

It is desirable that said vapour pipe be connected to said pipeline bymeans of a flexible hose and be mounted substantially in the middle ofthe refrigerant reservoir, said vapour pipe being pivoted at thislocation and adapted to make a pivotal movement by the action of acounterweight mounted opposite thereto.

Owing to this construction, the wearer of the protective garment whichconstitutes the present invention can incline and make other movements,there being no possibility for the liquid refrigerant to get into thevapour pipe. Further, this construction increases the range of garmentuse.

In one of the embodiments of the invention the vapour pipe is mounted inthe refrigerant reservoir by means of a ball and socket joint.

It is desirable that the pressure regulator incorporated in the pipelineconnecting the pneumatic pump with the gas cushion in the refrigerantreservoir be provided with a spring-loaded flexible element adapted tobe acted upon by refrigerant vapour pressure, said flexible elementbeing located in the pressure regulator housing and mounting a valveadapted for closing said pipeline.

The pressure regulator constructed according to this invention is moresensitive than that known in the prior art and can be adjusted while thegarment is being worn. It can be used advantageously under theconditions precluding the entry of liquid ammonia therein.

In another embodiment of the invention a refrigerant vapour pressurestabilizer is incorporated in said pipeline between the pressureregulator and, the pneumatic pump in order that the refrigerant vapourpressure be maintained constant irrespective of variation of the vapourpressure in the refrigerant reservoir.

In still another embodiment of the invention the pneumatic pumpcomprises a pneumatic pulse generator piped to the vapour pressurestabilizer and also comprises two spring-loaded diaphragms housed inindividual cases. Each diaphragm divides its case into two separatechambers one of which communicates with the pneumatic pulse generatorand the other with the pipeline connecting the suit pipes with the heatexchanger.

This constructional arrangement of the pneumatic pump stabilizes itsoutput and improves the operating dependability of the refrigeratingunit.

It is desirbale that the pneumatic pulses generator be constructed inthe form of a four-membrane pneumatic relay with two groups of pneumaticcontacts. This constructional arrangement reduces the size and weight ofthe pneumatic pump carried in the knapsack and improves its operatingdependability.

The gas and heat protective garment which constitutes the presentinvention enables the wearer to perform various physical activities,there being no possibility for liquid refrigerant to get into thepressure regulator and the pneumatic pump. This feature improves theoperating dependability of the protective garment.

Now the invention will be described in detail with reference to theaccompanying drawing in which:

FIG. 1 shows a general view of the gas and heat protective garmentaccording to the invention.

FIG. 2 is a diagrammatic view of the cooling system.

FIG. 3 is an enlarged view of the detail III of FIG. 1.

FIG. 4 is an enlarged view of the detail IV of FIG. 1.

FIG. 5 shows the attitude of the refrigerant reservoir and the vapourpipe therein, with the wearer inclined forward.

FIG. 6 shows same, with the wearer inclined backward.

The gas and heat protective garment is designed for emergency work inmines at temperatures up to in an atmosphere having no oxygen orcontaining noxious gases such as carbon oxide, hydrogen sulphide,sulphur dioxide and nitric oxide.

The garment comprises elastic fabric suit 1 (FIG. 1) made integral witha helmet, gloves (not shown) and socks (not shown). Mounted ont the suitoutside are pipes 2 for circulation of the cooling medium. The pipes aremade of elastic material, for example, polyvinyl chloride. The totallength of the pipes and their inside and outside diameters are chosen soas to provide for dissipating excessive heat from the wearers body andmaintain the temperature of the wearers body within permissible limits.The pipes 2 are harnessed to a manifold 3 constructed in the form of acircular tube. The manifold 3 is mounted on the helemet of the suit 1.The interior of the manifold 3 is divided by means of partitions intotwo parts, viz. an inlet section and an outlet section. The ends of thepipes 2 are connected one to each section of the manifold 3.

Adjoining the suit 1 is a knapsack 4 accommodating a respirationprotecting system and a refrigerating unit. The knapsack 4 has a rigidthin-walled caseS with a lid (not shown). Attached to the knapsack caseside nearest the wearers back are shoulder straps 6 and a belt (notshown).

The respiration protecting system is located in the upper (as shown)part of the knapsack 4. This system is essentially a self-containedoxygen breathing apparatus 7. It comprises a regenerating cartridge 8filled with a carbon dioxide absorbent, for example, calcium carbonateCa(OH)2. The regenerating cartridge 8 has a connecting piece 9 joined toa breathing bag 10 which is made of a gas-tight elastic material and hasa capacity sufiicient for normal breathing in performing physicalactivities. 7 Thebr eathing bag l fl is provided with a valve 11 thepurpose of which is to release excess air when the air pressure exceedsthe permissible limit and to prevent accumulation of nitrogen in thebag.

The breathing apparatus 7 also comprises an oxygen bottle 12 having ashut-off valve 13 connected to an oxygen feed device 14. Said oxygenfeed device comprises a pressure gauge (not shown), and a pressurereducer 15 with associated automatic and manual oxygen feed controlmechanisms. These mechanisms are housed in the same case to the pressurereducer l5 and are connected to the breathing bag 10 by means of aconnecting piece 16.

A connecting piece 17 provided on the top (as shown) part of theregenerating cartridge 8 receives a breathing hose 18 which incorporatesan inhalation valve 19. A connecting piece 20 provided on the bottom (asshown) part of the regenerating cartridge 8 receives a hose 21 whichincorporates an exhalation valve 22. Some distance from the regeneratingcartridge 8 the hoses 18 and 21 are connected to a hose 23 which inturn, is connected to a mask 24.

Mounted on the connecting piece 9 inside the breathing bag is a cooler25 for the air being inhaled. The air cooler 25 has a case 26 whichhouses a tubular heat exchanger 27. The heat exchanger 27 is connectedto the manifold 3 by means of a flexible hose 28 and is also connectedto a refrigerating unit 29 located in the lower part of the knapsack 4.The refrigerating unit 29, cooler 25, pipes 2, manifold 3 and connectinglines form the cooling system of the protective garment.

The refrigerating unit 29 comprises a reservoir 30 containing liquidrefrigerant to abstract heat from the cooling medium circulating in thepipes 2 of the suit 1. The reservoir 30 is connected by means of apipeline 31 to a pneumatic pump 32 which delivers the cooling medium tothe manifold 3 and the pipes 2 through a heat exchanger 33 built intothe reservoir 30. The refrigerant is liquid ammonia, the cooling mediumis water. The reservoir 30 constantly contains a gas cushion formed byrefrigerant vapour.

The reservoir 30 (FIG. 2) is constructed in the form of a cylinder withdished end plates. It is mounted in the case 5 (FIG. 1) of the knapsack4 and is adapted to be removed for charging with refrigerant. A chargingconnection 34 (FIG. 2) is provided in one of the reservoir end plates.

A valve 35 is fitted in the right (as shown) end plate of reservoir 30.The valve 35 has a body 36 (FIG. 3) fitted into a union 37 which iswelded to the reservoir end plate. The valve body 36 is held to theunion 37 by a nut 38, the joint between the two being made tight bymeans of a sealing ring 39.

The pipeline 31 which connects the refrigerant reservoir 30 with thepneumatic pump 32 is fitted to the valve 35 and incorporates arefrigerant vapour pressure regulator 40 (FIG. 2).

Mounted inside the refrigerant reservoir 30 is a vapour pipe 41 thepurpose of which is to supply refrigerant vapour to the pneumatic pump32. One end of the vapour pipe .41 extends above the level of therefrigerant in the reservoir 30. The intermediate portion of the vapourpipe 41 is made in the form of a flexible hose 42 (FIG. 3). The vapourpipe 41 is pivotally mounted in the middle of the reservoir 30 and isprovided with a counterweight 43 mounted in line with the extendingportion of the vapour pipe 41 and opposite thereto in relation to thepivot point.

The vapour pipe 41 is mounted in the refrigerant reservoir 30 by meansof a ball joint 44 comprising a spherical socket 45 to the lower (asshown) portion of which is fixedly mounted the counterweight 43, theextending portion of the vapour pipe 41 being mounted on the socket 45diametrically opposite to the counterweight 43.

The end of the vapour pipe 41 mounted on the socket 45 has a connectingpiece 46 to receive one end of the hose 42. The other end of the hose 42is fitted to a connecting piece 47 welded to the portion of the vapourpipe 41 which is fitted to the body 36 of the valve 35. The free end ofthis portion of the vapour pipe 41 is closed with a plug 48 madeintegral with a screw 49 the purpose of which is to mount the ball joint44.

The length of the hose 42 is chosen so that the portion of the vapourpipe 41 extending above the refrigerant level can pivot about the balljoint 44 through an angle of at least 180 in any plane in response toalteration of the attitude of the refrigerant reservoir 30 occurringwhen the wearer inclines.

The hose 42 is to be made of an elastic material proof against theeffects of liquid ammonia and offering the minimum possible resistanceto the pivoting action of the counterweight 43, these properties lastingthroughout the service life of the protecting garment.

Refrigerant vapour passes to the pneumatic pump 32 through the pipe 41,the valve 35 and the pipeline 31 in which is incorporated the pressureregulator 40 (FIG. 2).

A pressure regulator of the construction known in the prior art may beused, but it is more advantageous to employ the pressure regulatordescribed herein.

The pressure regulator 40 has a housing 50 (FIG. 4) with a threadedcover 51. The joint between the housing and cover is made tight by meansof a sealing ring 52. The housing 50 accommodates a bellows 53 which isa flexible element actuated by the pressure of the refrigerant vapour.The end of the bellows 53 facing to ward the cover 51 is closed with acover 54 which prevents the refrigerant vapour from entering thebellows. Mounted on the cover 54 is a valve 55 adapted to close thepipeline 31 which connects the housing 50 of the pressure regulator 40with the pneumatic pump 32 (FIG. 1). The pipeline 31 is connected to thepressure regulator cover 51 which is provided with a passage 56 for therefrigerant vapour to enter the housing 50. The cover 51 has a centralhole 57 into which is fitted a seat 58 for the valve 55. The centralhole 57 leads into a passage 59 provided for the refrigerant vapour topass from the pressure regulator housing 50 into the pipeline 31. Arecess 60 is provided in the cover 51 in line with the hole 57 for thepurpose of guiding the valve 55.

Located inside the bellows 53 and coaxially therewith is a spring 61bearing against a spring seat 62 which is recessed centrally to receivethe end of an adjusting screw 63. The adjusting screw 63 is threadedinto a nut 64 which serves the purpose of setting the tension of thepressure regulator spring 61 to the low limit of the refrigerant vapourpressure.

The nut 64 also has an external thread to screw into a cover 65 which isfitted onto the pressure regulator housing 50 and closes the bellows 53.The bellows end facing the nut 64 is secured in the pressure regulatorhousing 50. Upon adjusting the tension of the spring 61, the nut 64 isfixed in position relatively to the cover 65 by means of a locknut 66.To enable the wearer to adjust the tension of the spring 61, theadjusting screw 63 is connected to a flexible shaft 67 arranged toextend beyond the knapsack case 5 and provided with a knob at the end.

For the pressure of the refrigerant vapour entering the pneumatic pump32 to be maintained constant irrespective of the vapour pressure in therefrigerant reservoir 30, a pressure stabilizer 68 is interposed in thepipeline 31 between the pressure regulator 40 and the pneumatic pump 32.The constructional arrangement of the pressure stabilizer 68 is similarto that of the pressure regulator 40, except that the spring seat 62(FIG. 4) in the pressure stabilizer bears direct against the nut 64,there being no adjusting screw 63 and flexible shaft 67. Also the cover51 is provided with a passage (not shown) to which is connected apipeline 69 through which the refrigerant vapour is exhausted into theatmosphere for reducing the vapour pressure to the point required forthe operation of the pneumatic pump 32.

1n the gas and heat protection garment which constitutes the presentinvention a pneumatic pump of the construction known in the prior artmay be used. However, owing to the provision of the vapour pipe 41arranged to prevent liquid refrigerant from entering the pump, it ismore advantageous to employ a pump constructed as described hereinaftersince it gives a steady flow of the cooling medium through the pipes 2of the suit 1.

The pneumatic pump 32 (FIG. 1) comprises a pneumatic relay 70 (FIG. 2)the purpose of which is to generate pneumatic pulses. The pneumaticrelay 70 has a case 71 which houses a membrane assembly 72 composed ofmembranes 74, 75, 76 and 77 which are spaced apart and fixedly securedon a rod 73. The membranes and the case 71 form chambers A, B and C. Therod 73 is hollow and has seats 78 provided in its ends. Two partitions79, located one at each side of the membrane assembly 72 inside the case71 of the pneumatic relay 70, are fixedly secured parallel to themembranes. Each partition 79 has a central hole 80 formed coaxially withthe rod 73 and accommodating a seat 81.

Two valve plates 82 are mounted square with the rod 73, one at each endthereof. Each valve plate 82 is loaded by a spring 83 fitted between thevalve plate and the respective end wall of the case 71. The diameter ofthe valve plates 82 is slightly larger than the diameter of the seats81. Each valve plate 82 and is associated seats 81 and 79 form a groupof pneumatic contacts.

The partitions 79, case 71 and end membranes 74 and 77 form chambers D,E, G and H. The membranes 74, 75, 76 and 77 have different effectiveareas (the areas acted upon by the pressure of the working medium in therespective chamber of the pneumatic relay 70). The effective areas ofthe membranes and the relationship therebetween are chosen according tothe diameters of the seats 78 and 81 and the pressure of the workingmedium in each of the chambers of the pneumatic relay 70. The effectiveareas of the membranes 74 and 77 are equal. The effective area of themembrane 75 is approximately 1.5 times that of the membrane 74 or 77.The effective area of the membrane 76 is 2.5 times that of the membrane75. r

The interior of therod 73 communicates with the chamber A by means of ahole provided in the rod 73 between the membranes 74 and 75. The chamberA is connected to the pressure stabilizer 68 by means of the pipeline31.

The pneumatic pump 32 (FIG. 1) also comprises two cases 84 (FIG. 2)housing elastic diaphragms 85. The edge of each diaphragm 85 is securedall the way around in the case 84. The left (as shown) case 84 isdivided by the diaphragm into two separate chambers K and L. The right(as shown) case 84 is divided by the diaphragm into two separatechambers M and N. The chambers K and N are connected by means ofpipelines 86 and 87 respectively with the chambers E and G of thepneumatic relay 70. The pipeline 86 is connected through a pipeline 88to the chamber C. The pipeline 87 is connected through a pipeline 89 tothe chamber B. Each of the pipelines 88 and 89 incorporates a valve 90.The chambers D and H of the pneumatic relay 70 communicate with theatmosphere through pipelines 91 and 92 in order to let out the vapourexhausted from the pneumatic pump 32. The aforementioned pipeline 69 isconnected to the pipeline 91.

The upper (as shown) part of each case 84 is provided with a connectingpiece 93 positioned square with the diaphragm 85. Located in each case84 coaxially with the connecting piece 93 is a spring 94 one end ofwhich bears against the diaphragm 85 and the other end bears againstcircular projection (not shown) provided inside the connecting piece 93.

The connecting pieces 93 are joined to a pipeline 95 which incorporatesdelivery valves 96, one for each diaphragm 85. The connecting pieces 93are also joined to a flexible pipeline 97 which connects to the manifold3 of the suit 1. Some distance from the connecting pieces 93 thepipeline 97 divides into branches supplying the cooling medium, whichcirculates in the pipes 2 of the suit 1, to the chambers L and M of thepneumatic pump 32. Each branch of the pipeline 97 incorporates a suctionvalve 98. A pipe 99 fitted to the pipeline between the valves 96connects the pipeline 95 to the heat exchanger 33 located in therefrigerant reservoir 30. The heat exchanger 33 is connected through ahose 100 to the aforementioned heat exchanger 27 of the respirationprotecting system.

For convenience in use, the flexible hose 28, which connects themanifold 3 of the suit 1 with the heat exchanger 27, and the pipeline97, which connects the mainfold 3 with the pneumatic pump 32, areprovided with hermetically sealed connection members (not shown) whichenable the suit, respiration protecting system and refrigerating unit tobe kept filled with the cooling medium during storage.

The suit 1 and the knapsack 4 are completely enclosed with a three-layerheat insulating cover 101 (FIG. 1). This cover includes an outer layer102 of a heat-resistant fabric with a metallized coating, an inner layer103 of a rubberized fabric and layer 104 of soft polyurethane foamsandwiched between said layers 102 and 103. At the wearers face thecover 101 has a window 105 made of heat resisting and rejecting glass.

The initial state of the components of the protective garment beforeputting it on is as follows:

The regenerating cartridge 8 is filled up with carbon dioxide absorbent.The bottle 12 is charged with oxygen and the bottle valve .13 is shutoff.

The reservoir 30 is filled up with liquid refrigerant. The reservoirvalve 35 is shutoff. The pipes 2, manifold 3, hose 28, heat exchangers27 and 33, chambers L and M, connecting pieces 93, pipeline 95 andflexible pipeline 97 are filled up with coolant.

The pressure regulator 40 is adjusted preliminarily. For the purpose theadjusting screw 63 is turned all the way out. The nut 64 is fixed bymeans of the locknut 66 in the position where the valve 55 can open onlywhen the refrigerant vapour pressure acting on the bellows 53 is atleast 4.5 kg/cm, inasmuch as at a lower vapour pressure the boilingpoint of liquid ammonia approaches 0 C, under which conditions the watercontained in the heat exchanger 33 is likely to freeze. When adjustingthe pressure regulator finally before the beginning of the operation,the adjusting screw 63 is to be turned all the way in.

The pressure stabilizer 68 is set to the vapour pressure required forthe operation of the pneumatic pump 32. The surplus refrigerant vapouris exhausted through the pipeline 69 into the atmosphere.

The diaphragms 85 of the pneumatic pump 32 are in the lowermost (asshown) position, each being held by the spring 94 against the case 84.

After the wearer has been dressed in the suit 1 complete with theknapsack 4, a checkover is made on the performance of the respirationprotecting system. For the purpose the mask 24 is put on and the valve13 of the bottle 12 is turned on for the oxygen to pass from the bottle12 through the feed device 14 into the breathing bag 10. The exhaled airpasses through the hoses 23 and 21 into the regenerating cartridge 8where carbon dioxide is absorbed. Therefrom the purified air passesthrough the connecting piece 9 into the breathing bag 10, coming incontact with the heat exchanger 27 of the cooler 25. In the breathingbag the air mixes with oxygen and on inhalation, again coming in contactwith the heat exchanger 27, passes through the hose 18, valve 19, hose23 and mask 24 to be breathed During the breathing the oxygen feeddevice 14 automatically feeds the required quantity of oxygen into thebreathing bag 10.

If there is an excess of the air in the breathing bag 10, valve 11 opensautomatically and part of the air is exhausted into the atmosphere,whereby accumulation of nitrogen is prevented.

After checking the respiration protecting system, the cooling system ischecked up. For the purpose the valve 35 of the refrigerant reservoir 30is turned on, permitting the refrigerant vapour to pass through thevapour pipe 41, the connecting piece 46, the hose 42 and the otherportion of the vapour pipe 41 into the body 36 of the valve 35 andthence via the pipeline 31 into the housing 50 of the pressure regulator40.

As the refrigerant vapour comes into the housing 50, the vapour pressuretherein rises. At the same time the adjusting screw 63 is manipulated bymeans of the knob attached to the flexible shaft 67, said screw 63 beingturned out until the load of the spring 61 holding the valve 55 againstits seat 58 is overcome by the refrigerant vapour pressure exerted onthe bellows 53. With these conditions obtained, the valve 55 becomesunseated stabilizer therefrigerant vapour passes by way of the hole 57provided in the seat 58 into the passage 59 and thence via the pipeline31 into the pressure stabilizer 68.

The pressure stabiliser 68 has been set to the refrigerant vapourpressure required for the operation of the pneumatic pump 32. As a rule,this pressure is considerably lower than the vapour pressure in therefrigerant reservoir 30. Therefore, when the pressure of therefrigerant vapour in the stabilizer 68 rises, it compresses the bellowsagainst the load of the spring, unseating the valve and therebypermitting the vapour to be vented tinto the atmosphere through thepipeline 69. The exhaust continues until the vapour pressure drops tothe stabilizer setting. Practically, the vapour exhaust is constant.From the pressure stabilizer 68 the refrigerant vapour passes by way ofthe pipeline 31 into the chamber A of the pneumatic relay 70 and intothe interior of the rod 73. Since the effective area of the membrane 75is larger than that of the membrane 74, the former is acted upon by agreater vapour pressure and is caused to deflect to the right (asshown), moving the rod 73 in the same direction. The rod 73 leaves theleft (as shown) valve plate 82, whereby the chamber E is put incommunication with the rod interior. The rod 73 comes up against theright valve plate 82 and, moving further against the load of the spring83, shifts the valve plate 82 to the right and off the seat 81, therebyputting the chamber G in communication with the chamber H and,consequently, with the atmosphere.

From the chamber E the refrigerant vapour passes through the pipeline 86into the chamber K in the left diaphragm case 84. The pressure of therefrigerant vapour causes the diaphragm 85 to move upward (as shown)against the load of the spring 94, forcing out the cooling medium fromthe chamber L through the delivery valve 96 into the pipeline 85.Therefrom the cooling medium passes via the pipe 99 into the heatexchanger 33 where it cools off. Thence the cooling medium passes viathe pipeline 100 into the heat exchanger 27 located in the breathing bag10 and from there flows through the hose 28 into the manifold 3 andthence into the pipes 2 of the suit 1.

While passing into the chamber K of the diaphragm case 84, therefrigerant vapour also passes through the pipeline 88 and the valve 90into the chamber C of the pneumatic relay (the valve 90 is set to allowthe refrigerant vapour to flow at a rate much lower than the rate offlow through the pipeline 86). Since the effective area of the membrane76 is larger than the sum of the effective areas of the membranes 77 and75, the pressure of the refrigerant vapour causes the membrane 76 tomove to the left (as shown), bringing the rod 73 against the left valveplate 82. Moving further against the load of the spring 83, the rod 73shifts the valve plate 82 to the left and off its seat 82, therebyputting the chamber E in communication with the chamber D. Consequently,the chamber K communicates with the atmosphere through the pipelines 86and 91 and the chamber C communicates with the atmosphere through thepipelines 88, 86 and 91. When moving to the left, the rod 73 leaves theright valve plate 82 and the latter, under the action of the spring 83,closes the seat 81. As a result, the chamber G is isolated from thechamber H and, consequently, from the atmosphere, whereas the interiorof the rod 73 is put in communication with the chamber G. Therefrigerant vapour passes via the pipeline 83 and the interior passagein the rod 73 into the chamber N, at the same time passing via thepipeline 89 and the valve 90 into the chamber B of the pneumatic relay70. The pressure of the refrigerant vapour causes the diaphragm to moveupward (as shown) against the load of the spring 94, forcing out thecooling medium through the delivery valve 96 into the pipeline 95,wherefrom it passes through the pipe 99 into the heat exchanger 33. m

This condition continues until the vapour pressure exerted on themembrane 76 overcomes the vapour pressure exerted on this membrane fromthe chamber G, which is open to the atmosphere during this period.

As the vapour pressure in the chambers K, E and C drops, the left (asshown) diaphragm returns into the initial position under the action ofthe spring 94, drawing in the cooling medium from the suit pipes 2, thecooling medium coming via the manifold 3, the pipe line 97 and the valve98. Thus, the suction stroke of the left diaphragm 85 occurssimultaneously with the delivery stroke of the right diaphragm 85.

When the pressures exerted on the membrane 76 from the chambers B and Chave become equal, the rod 73 is moved to the right due to the vapourpressure acting on the membrane 75, since the refrigerant vapour entersthe chamber A constantly. The operating cycle of the pneumatic pump 32is repeated, i.e., during the discharge stroke of the left diaphragm 85the right diaphragm 85 makes a suction stroke. Inasmuch as thediaphragms 85 move in anti-phase and the pressure of the refrigerantvapour entering the chamber A of the pneumatic relay 70 is constant thecooling medium moves in a steady flow throughout the cooling systemirrespective of variation of the vapour pressure in the refrigerantreservoir 30 during the wearers activities.

After the checks on the breathing and cooling systems have beencompleted, the heat insulating cover 101 is put over the suit 1 and theknapsack 4.

During the wearers activities the breathing and cooling'systems operateas described hereinbefore. Owing to the wearers movements, the knapsackand, consequently, the refrigerant reservoir 30 change their attitude,the surface of the liquid refrigerant contained in the reservoir 30remaining horizontal. The portion of the vapour pipe 41 connected to thevalve 35 follows the movement of the refrigerant reservoir 30, the otherportion of said vapour pipe 41, which extends above the level of therefrigerant and is mounted on the socket 45 of the ball joint 44attached to the free end of the first-mentioned portion of the vapourpipe 41, being kept vertical by the action of the counterweight 43attached to the opposite side of said socket 45, the provision of theflexible hose 42 enabling the extending portion of said vapour pipe 41to pivot about the ball joint 44. Referring to FIGS. 5 and 6, saidportion of the vapour pipe 41 is always kept vertical, extending abovethe level of the liquid refrigerant irrespective of the attitude of therefrigerant reservoir 30. Thereby the liquid refrigerant is preventedfrom getting into the vapour pipe 41 to preclude its waste, improve theoperating dependability of the pneumatic pump 32 and increase the rangeof use of the protective garment which constitutes the presentinvention.

What is claimed is:

1. A gas and heat protective garment comprising: a heat insulatingcover; a suit provided with pipes for circulation of a cooling medium; aknapsack accommodating a respiration protecting system and arefrigerating unit, said suit and said knapsack being enclosed with saidheat insulating cover; said refrigerating unit comprising: a reservoirwith a liquid refrigerant contained therein and a heat exchanger, saidreservoir and heat exchanger serving the purpose of abstracting heatfrom said cooling medium circulating in said pipes of said suit, apneumatic pump actuated by refrigerant vapour, a pipeline connectingsaid pneumatic pump with' a gas cushion in said refrigerant reservoir, apressure regulator incorporated in said pipeline, a vapour pipe forminga part of said pipeline, a portion of said vapour pipe being arranged toextend above the level of the liquid refrigerant contained in saidreservoir, said extending portion of the vapour pipe being movablymounted in the refrigerant reservoir and adapted to remain in a verticalposition when said refrigerant reservoir changes its attitude, thisconstructional arrangement permitting only refrigerant vapour to pass tosaid pneumatic pump.

2. A gas and heat protective garment as claimed in claim 1 in which saidvapour pipe is connected to said pipeline by means of a flexible hoseand is mounted substantially in the middle of said refrigerantreservoir, said vapour pipe being pivoted at this location and adaptedto make a pivotal movement by the action of a counterweight mountedopposite thereto.

3. A gas and heat protective garment as claimed in claim 2, in whichsaid vapour pipe is mounted in said refrigerant reservoir by means of aball and socket joint.

4. A gas and heat protective garment as claimed in claim 1, in whichsaid pressure regulator is provided with a spring-loaded flexibleelement adapted to be acted upon by refrigerant vapour pressure, saidflexible element being located in the pressure regulator housing andmounting a valve adapted for closing said pipeline connecting thepneumatic pump with the gas cushion in the refrigerant reservoir.

5. A gas and heat protective garment as claimed in claim 4, in which apressure stabilizer is incorporated in said pipeline between thepressure regulator and the pneumatic pump in order that the pressure ofthe refrigerant vapour entering the pneumatic pump be maintainedconstant irrespective of variation of the vapour pressure in therefrigerant reservoir.

6. A gas and heat protective garment as claimed in claim 5, in whichsaid pneumatic pump comprises a pneumatic pulse generator piped to saidpressure stabilizer and includes two spring-loaded diaphragms housed inindividual cases, each diaphragm dividing its case into two separatechambers one of which communicates with the pneumatic pulse generatorand the other with the pipeline connecting the suit pipes with the heatexchanger.

7. A gas and heat protective garment as claimed in claim 6, in whichsaid pneumatic pulse generator is constructed in the form of afour-membrane pneumatic relay with two groups of pneumatic contacts.

a e a:

1. A gas and heat protective garment comprising: a heat insulatingcover; a suit provided with pipes for circulation of a cooling medium; aknapsack accommodating a respiration protecting system and arefrigerating unit, said suit and said knapsack being enclosed with saidheat insulating cover; said refrigerating unit comprising: a reservoirwith a liquid refrigerant contained therein and a heat exchanger, saidreservoir and heat exchanger serving the purpose of abstracting heatfrom said cooling medium circulating in said pipes of said suit, apneumatic pump actuated by refrigerant vapour, a pipeline connectingsaid pneumatic pump with a gas cushion in said refrigerant reservoir, apressure regulator incorporated in said pipeline, a vapour pipe forminga part of said pipeline, a portion of said vapour pipe being arranged toextend above the level of the liquid refrigerant contained in saidreservoir, said extending portion of the vapour pipe being movablymounted in the refrigerant reservoir and adapted to remain in a verticalposition when said refrigerant reservoir changes its attitude, thisconstructional arrangement permitting only refrigerant vapour to pass tosaid pneumatic pump.
 1. A gas and heat protective garment comprising: aheat insulating cover; a suit provided with pipes for circulation of acooling medium; a knapsack accommodating a respiration protecting systemand a refrigerating unit, said suit and said knapsack being enclosedwith said heat insulating cover; said refrigerating unit comprising: areservoir with a liquid refrigerant contained therein and a heatexchanger, said reservoir and heat exchanger serving the purpose ofabstracting heat from said cooling medium circulating in said pipes ofsaid suit, a pneumatic pump actuated by refrigerant vapour, a pipelineconnecting said pneumatic pump with a gas cushion in said refrigerantreservoir, a pressure regulator incorporated in said pipeline, a vapourpipe forming a part of said pipeline, a portion of said vapour pipebeing arranged to extend above the level of the liquid refrigerantcontained in said reservoir, said extending portion of the vapour pipebeing movably mounted in the refrigerant reservoir and adapted to remainin a vertical position when said refrigerant reservoir changes itsattitude, this constructional arrangement permitting only refrigerantvapour to pass to said pneumatic pump.
 2. A gas and heat protectivegarment as claimed in claim 1 in which said vapour pipe is connected tosaid pipeline by means of a flexible hose and is mounted substantiallyin the middle of said refrigerant reservoir, said vapour pipe beingpivoted at this location and adapted to make a pivotal movement by theaction of a counterweight mounted opposite Thereto.
 3. A gas and heatprotective garment as claimed in claim 2, in which said vapour pipe ismounted in said refrigerant reservoir by means of a ball and socketjoint.
 4. A gas and heat protective garment as claimed in claim 1, inwhich said pressure regulator is provided with a spring-loaded flexibleelement adapted to be acted upon by refrigerant vapour pressure, saidflexible element being located in the pressure regulator housing andmounting a valve adapted for closing said pipeline connecting thepneumatic pump with the gas cushion in the refrigerant reservoir.
 5. Agas and heat protective garment as claimed in claim 4, in which apressure stabilizer is incorporated in said pipeline between thepressure regulator and the pneumatic pump in order that the pressure ofthe refrigerant vapour entering the pneumatic pump be maintainedconstant irrespective of variation of the vapour pressure in therefrigerant reservoir.
 6. A gas and heat protective garment as claimedin claim 5, in which said pneumatic pump comprises a pneumatic pulsegenerator piped to said pressure stabilizer and includes twospring-loaded diaphragms housed in individual cases, each diaphragmdividing its case into two separate chambers one of which communicateswith the pneumatic pulse generator and the other with the pipelineconnecting the suit pipes with the heat exchanger.